Automatic steering systems for agricultural vehicles may include a guidance module with a Global Positioning System (GPS) receiver and a microprocessor adapted to process and store GPS data defining travel paths, or swath paths. The swath paths can be associated with a cultivated field in an agricultural vehicle application. An automatic steering module is connected to the guidance module to steer the vehicle, e.g., via a primary hydrostatic steering system.
Accurate vehicle and specialized farming equipment guidance is used in agricultural applications, for example, tilling, planting, spraying, fertilizing, harvesting and other farming operations. Such implements may be operated and applied by repeatedly traversing cultivated fields. Ideally, the equipment is guided through accurately-spaced passes or swaths, the spacing of which is determined by the swath width of the equipment. Gaps and overlaps in the swath paths may occur when operators deviate from the ideal guide paths, resulting in under-coverage and over-coverage respectively. Such gaps and overlaps may be a concern for certain agricultural operations, for example, by reducing crop yields. Previous systems for assisting with the guidance of agricultural equipment include foam markers, which deposit foam along the swath edges.
Currently automatic guidance systems on agricultural vehicles are pre-programmed with standardized guidance patterns, e.g., straight, curved, circular and spiral. Those existing standardized guidance patterns are inadequate to accommodate a swath path of a tractor and baler implement for harvesting narrow windrows. While harvesting windrows with a baler implement, operators must slowly maneuver the tractor back and forth in a windrow to maintain an even distribution of material in the chambers of the baler implement. Sensors for detecting the shape of a bale have been developed to give steering information to the operator, but the operator relies upon a manual steering operation to form evenly distributed material density and shapes of bales. By maintaining an even distribution of material in the baler implement, the resulting bales produced by the baler implement are of optimal size and density. GPS automatic guidance systems alone are not capable of maneuvering the tractor in a back and forth pattern along a windrow.
Therefore there is a need for an automatically guided agricultural vehicle that can produce bales of evenly distributed material and density, and having a desired shape.